On day one I had to use the Fallout Beta as I use XAudio drivers which cause a 10 min crash and one gameplay bug where a quest related script did not fire. I reloaded and did the quest again (It was early on and very short) so problem solved. I really do not mind though, rather play it with a few bugs than wait till it was bug free.

Well, I played both Fallout 3 and Fallout 4 recently and i can say that 4 is amazing! and much better than 3
I have 105 hours in Fallout 3 on Steam and
98 hours for Fallout 4 and I have explored easily under 1/4 of the game.